Paranasal sinuses are cavities formed within the bones of the face that are accessible via an individual's nasal cavity. The paranasal sinuses include the frontal sinuses, the sphenoid sinuses, the ethmoid sinuses, and the maxillary sinuses. The paranasal sinuses are lined with mucous-producing epithelial tissue.
Normally, mucous produced by the linings of the paranasal sinuses slowly drains out of each sinus through an opening known as an ostium. Some conditions, however, can interfere with the drainage of the mucous. If the mucous does not drain properly or other abnormal anatomic variations exist, sinus disorders (e.g., a sinus infection) can result. Some of the conventional systemic methods for treating these sinus disorders can result in cutaneous rash, diarrhea, bacterial resistance from antibiotic use, adrenal suppression, weight gain from steroid medications, hypertension, and sleep disturbance from decongestant use.